Grinding or polishing wheel



(No Model.)

0. V. HUNT. GRINDING 0R POLISHING WHEEL.

Patented May 30, 1882.

FIG, 5.

Nv PUERSI Fhala-Lilhogr-phun Washington, D. c.

EINTTED STATES PATENT OFFICE.

CHARLES V. HUNT, OF PHILADELPHIA, PENNSYLVANIA.

GRINDING OR POLISHING WHEEL.

SPECIFICATION forming part of Letters Patent No. 258,760, dated May 30,1882.

Application filed March 27, 1882.

To all whom it may concern.

Be it known that LOHARLEsV. HUNT, asubject of the Queen of Great Britainand Ireland, and a resident of Philadelphia, Pennsylvania, haveinventedcertain Improvements in Grinding or Polishing Wheels, of which thefollowing is a specification.

My invention relates to certain improvements in that class of grindingor polishing wheels in which the emery is secured by glue or cement tothe periphery of a wheel or disk, the object of my invention being toproduce a more durable wheel than usual, and one which will retain itstruth.

In the accompanying drawings, Figure 1 is a sectional view of anordinary wheel of the class to which my invention relates; Fig. 2, aperspective view, partly in section, of my improved wheel Fig. 3, avertical section of the same, and Figs. 4 and 5 views illustrating amodification of the invention.

The usual plan of making grinding or p01- ishing wheels is to first turnin a lathe a wooden disk, A, Fig. l, and then to secure to the peripheryof this disk a strip, A, of leather, the latter being the medium forreceiving and retaining the granular grinding or polishingmaterial-usually e1nery--whieh is secured to the leather ring by glue orother suitable cement. A wheel of this sort is not durable and will notretain its truth, unequal expansion and contraction rendering the wheelunreliable in both of these respects.

My improved wheel (shown in Figs. 2 and 3) comprises a central metallichub, a, with radial arms I) and a rim, d, thelatterin the presentinstance having a flatperiphery. In practice, however, the periphery maybe made convex, concave, or of any other shape which the character ofthework to be performed may suggest.

To the rim of the wheel is adapted an annular sheet, B, of leather,which is caused to tightly embrace said rim by means of lacings ff,adapted to openings in the hub a and in the overlapping portions of thestrip B.

Annular side plates, D D, are then applied to the wheel, one of theseplates being clamped beween the hub of the wheel and a flange, g, onasleeve, F, which forms the bushing for the wheel. The other plate isclamped between the hub of the wheel and a nut, h, on the sleeve F, andboth plates are made concavo-convex, as shown in Fig. 3, so that theirouter edges (No model.)

will bear upon and press inward the overlapping portions of the strip B,thereby forming a water-tightjoint.

The wheel thus constructed is strong and durable, and has no tendency tobecome irregular from use, the concentration of the weight at and nearthe driving shaft or spindle overcoming any tendency to fracture owingto contrifugal force, and insuring the steady running of the wheel atthe high speed necessary for performing its intended work.

In the modification of the invention shown in Figs. 4 and 5 a centraldisk-wheel, of wood, takes the place of the wheel shown in Figs. 2 and3, and the lacings pass round hooks on ringsv 1', adapted to the hub ofthe diskwheel, the construction of the wheel in other respects being thesame as that above described. The use of the wooden disk-wheel rendersthe wheel lighter than that shown in Figs. 2 and 3, and in view of thisfact the modified wheel may in some cases be preferred.

The use of the side plates,DD,in this wheel is of importance, as thetight joint between the edges ot'said wheel and the leather covering Bprevents the access of moisture to the wooden diskwheel. In the modifiedwheel the bushing F- is necessary; but in the wheel shown in Figs. 2 and3 this bushing may, if desired, be dispensed with, threaded projectionsbeing formed on the hub a, and the annular plates D being thickened atthe center and threaded internally for adaptation to said threadedprojections of the huh.

I claim as my invention-- 1. The combination of the central wheel, thecovering-strip B, and lacings f, whereby said covering-strip is drawnover the rim of the said wheel, as set forth.

2. The combination of the central wheel, the covering-strip B, thelacings f, and the side plates, D D, as'specitied.

3. The combination of the central wheel, the covering B, the laeings f,the side plates, D, and the bushing F, with flange g and nuth, asspecified.

In testimony whereof I have signed my name to this specification inthcpresence of two subscribing witnesses.

OHARLES V. HUNT.

